Tokyo Antiquarian Booksellers' Cooperative Association

The Tokyo Antiquarian Booksellers' Cooperative Association (東京都古書籍商業協同組合), commonly known as Tokyo Koshokumiai (東京古書組合), is a cooperative association of second-hand and antiquarian booksellers licensed by the Tokyo Metropolitan Government. Its roots reach back to 1916, when the Tokyo Koshokumiai Club was built on the site of the present Tokyo Koshokumiai Hall in Kanda Ogawamachi, Chiyoda-ku, Tokyo. A booksellers' association was formed there in 1920 with more than 400 members, was licensed as a quasi-rule cooperative by Tokyo Prefecture in 1931, and was reorganized as the Tokyo-to Koshoseki Shogyo Kyodo Kumiai in 1944. The cooperative itself was formally established and licensed by the Tokyo Metropolitan Government on September 11, 1947. The association's core business is the operation of the antiquarian book market (kōkaikai), where member dealers trade general, specialist, Western, Japanese, Chinese and manuscript materials. These markets are held almost daily at the Tokyo Koshokumiai Hall and at branch halls, and they are the mechanism by which market prices for used books are formed. Beyond the market, the cooperative provides information on the antiquarian trade, promotes knowledge and appreciation of old books, operates shared facilities and group purchasing, and publishes the bimonthly organ magazine 'Kosho Geppō' (古書月報). In 1996 the cooperative launched 'Nihon no Koshoten' (日本の古本屋), one of Japan's earliest online antiquarian book search sites, which consolidated the individual websites of member shops into a single nationwide search and mail-order platform. The site is operated by the Tokyo cooperative but is designed for national scale, with participation by shops belonging to the National Federation of Antiquarian Booksellers' Cooperatives (Zenkoshoren). It lists modern and contemporary rare materials, periodicals, hobby books, Edo-period and earlier Japanese books and manuscripts, and Chinese, Korean, European and American antiquarian and classical books, making it one of the largest antiquarian book search sites in Japan. By May 2026 the database exceeded 7 million items and monthly orders surpassed 60,000. Membership is open to small-scale operators licensed as antique dealers by the Tokyo Metropolitan Public Safety Commission and dealing mainly in antiquarian books, with a place of business in Tokyo. Membership stood at 507 as of the end of May 2026 (Reiwa 8), organized into seven branches including the Kanda branch, home of the Tokyo Koshokumiai Hall. The cooperative marked its 100th anniversary in 2020 and published 'Tokyo Koshokumiai Hyakunen-shi' (A Hundred-Year History of the Tokyo Antiquarian Booksellers' Cooperative) in 2021.

The institutional history of the Tokyo Antiquarian Booksellers' Cooperative Association begins in the Taishō era. In August 1916, the Tokyo Tosho Club (東京図書倶楽部) was newly built on a corner of the present site in Kanda Ogawamachi, laying the groundwork for the later association. In January 1920, the Tokyo Antiquarian Booksellers' Association (東京古書籍商組合) was founded at the Tokyo Tosho Club with more than 400 members. In 1931 (Shōwa 6), that association was licensed by Tokyo Prefecture as a quasi-rule cooperative (準則組合). In 1944 (Shōwa 19) it was reorganized as the Tokyo-to Koshoseki Shogyo Kyodo Kumiai (東京都古書籍商業協同組合). The cooperative in its present legal form was established and licensed by the Tokyo Metropolitan Government on September 11, 1947 (Shōwa 22). For most of its existence the cooperative's central function has been the operation of the antiquarian book market, or exchange fair (交換会). Because individual antiquarian bookshops tend to be highly specialized, the market allows member dealers to trade general books, specialist books, Western books, Japanese books, Chinese books and documentary magazines across genres. Markets are held almost daily at the Tokyo Koshokumiai Hall and at branch halls, and the cooperative states that market transactions, rather than individual shops, determine the going prices for used books. The cooperative's nationwide network is described as forming a system that delivers rare books into the hands of the people who genuinely need them. In 1996 (Heisei 8), the cooperative launched the antiquarian book search site 'Nihon no Koshoten' (日本の古本屋), one of the earliest such sites in Japan. It consolidated the websites that individual antiquarian bookshops had previously operated into a single online platform, enabling search and mail-order sales across a wide range of fields. Although operated by the Tokyo cooperative, the site aims at national scale and is open to antiquarian bookshops belonging to the National Federation of Antiquarian Booksellers' Cooperatives (Zenkoshoren). It lists modern and contemporary rare materials, documentary magazines, hobby materials, Edo-period and earlier 'wahon' and 'shahon' manuscripts, and Chinese, Korean, European and American antiquarian and classical books, and is described as one of the largest antiquarian book search sites in Japan. As awareness grew, the volume of listings increased year by year; by May 2026 the amount of antiquarian book data exceeded 7 million items and monthly orders exceeded 60,000. The name 'Nihon no Koshoten' is also used as a unified designation for antiquarian bookshops belonging to Zenkoshoren. Organizationally, the cooperative had seven branches as of 2010 and 630 members as of 2015. Membership requires being a small-scale operator licensed as an antique dealer by the Tokyo Metropolitan Public Safety Commission and dealing mainly in antiquarian books, with a place of business in Tokyo. A survey in the 2000s found that 70 percent of members had annual sales of 10 million yen or less. As of the end of May 2026 (Reiwa 8), membership stood at 507, organized into seven branches including the Kanda branch, where the Tokyo Koshokumiai Hall is located. The cooperative marked its 100th anniversary in 2020, and in 2021, as part of the commemorative projects, published 'Tokyo Koshokumiai Hyakunen-shi' (A Hundred-Year History of the Tokyo Antiquarian Booksellers' Cooperative). Its stated activities include operating the market for antiquarian books handled by members, establishing and maintaining shared facilities (halls), joint purchasing of business supplies used by members, joint appraisal of antiquarian books, education and information provision for members, member welfare projects, publication of the bimonthly organ magazine 'Kosho Geppō', and activities to improve the image of the antiquarian book trade.

• 2026

  As of the end of May, membership stood at 507 and the 'Nihon no Koshoten' database exceeded 7 million items with over 60,000 monthly orders.

• 2021

  Published 'Tokyo Koshokumiai Hyakunen-shi' as part of the anniversary projects.

• 2020

  Marked its 100th anniversary.

• 1996

  Launched the 'Nihon no Koshoten' antiquarian book search site.

• 1947

  Established and licensed by the Tokyo Metropolitan Government on September 11.

• 1944

  Reorganized as the Tokyo-to Koshoseki Shogyo Kyodo Kumiai.

• 1931

  The association licensed by Tokyo Prefecture as a quasi-rule cooperative.

• 1920

  Tokyo Antiquarian Booksellers' Association founded at the Tokyo Tosho Club with more than 400 members.

• 1916

  Tokyo Tosho Club built on the present site in Kanda Ogawamachi, laying the groundwork for the association.

A member-owned cooperative and trade body for Tokyo's antiquarian booksellers, acting as the market-making and online-retail infrastructure for Japan's used-book trade.

• Nihon no Koshoten (日本の古本屋)

  An online antiquarian book search and mail-order site launched in 1996, operated by the Tokyo cooperative and open to Zenkoshoren member shops nationwide.

• Antiquarian book markets (kōkaikai)

  Member-only exchange fairs held almost daily at the Tokyo Koshokumiai Hall and branch halls, where prices for used books are formed.

• Kosho Geppō (古書月報)

  The cooperative's bimonthly organ magazine, informing members of association activities.

• Tokyo Koshokumiai Hall

  The cooperative's shared facility in Kanda Ogawamachi, home to the Kanda branch and a venue for markets and events.

1. 1東京古書組合 公式ウェブサイトkosho.ne.jp
2. 2組合の歴史・活動内容kosho.ne.jp
3. 3Tokyoto Koshoseki Shogyo Kyodo Kumiai (Wikidata)wikidata.org
4. 4東京都古書籍商業協同組合 (Wikipedia)ja.wikipedia.org